You can say one is 1st generation immigrant, and other is 2nd gen: https://en.wikipedia.org/wiki/Immigrant_generations

Sorry, but I need to push back against this sentiment. Where is the limit? It strikes me as exclusionary, and many other young, educated Germans have agreed with me on this specific point. When I lived in California, I met Chinese Americans who had lived in the United States longer than my family (1850s, 5+ generations). With a purely reductionist view, does everyone remain an immigrant in the United States ad infinitum except Native Americans? Is that also true in Malaysia, Canada, Peru, Taiwan, Brazil, New Zealand, Fiji, and Australia from their/your cultural view? It strikes me as "Ad Absurdum". To really stir the pot: Considering the recent Black Lives Matter movement, are all African descent people absolutely and continuously for all eternity "immigrants" where ever they live away from the African continent? Repeat for the descendents of the Indian subcontinent, whom form one of the largest diasporas in human history. I have watched and read multiple interviews with Özlem Türeci, and, each time, she specifically pushes back against this posturing: "Oh, but you are 'truly' Turkish."

They are part of the Turkish diaspora in Germany. Wouldn’t know about the exact birth details but they played substantial role in the vaccination program in Turkey.

They also wrote a book

Nice tip! I didn't know about it. I found this: https://us.macmillan.com/books/9781250280374

<< The Vaccine: Inside the Race to Conquer the COVID-19 Pandemic

Author: Joe Miller with Dr. Özlem Türeci and Dr. Ugur Sahin >>

Interestingly both last names are written incorrectly on the cover (should have been TÜRECİ and ŞAHİN -- with a dotted capital I). Looks like a bug in the "convert to all caps" function of their publishing or design software. It can't be a font issue as they were able to print "Ğ".